This invention relates to a rotary cam assembly and, more particularly, to a rotary cam assembly applicable to a throttle valve unit for displacing the pressure regulating means of throttle valves, which are arranged in the hydraulic circuit of an automatic transmission used in an automotive vehicle, in correspondence with the degree of throttle opening of an engine.
A rotary cam assembly generally comprises, taking a plate cam as an example, a cam surface formed on outer side of the cam, a cam follower, or contacting element, which contacts the cam surface for being reciprocatively displaced thereby, and an input member for rotating the cam plate.
An example of a rotary cam assembly applied to a throttle valve unit is as illustrated in FIGS. 15A and 15B. As shown, a plate cam 100 is formed to include a cam surface 101 on a portion of its outer periphery, a circular groove 102 in the remaining portion of its outer periphery, the groove 102 and the cam proper sharing the same center, and a center hole 103. A wire 110 has one end anchored at the left end of the groove 102 and has a portion of its length laid in the groove to form an input member. A fixed member 120 is provided with a support shaft 121 on which the cam plate 100 is rotatably mounted at its center hole 103. The fixed member 120 supports a plunger 130 capable of being slidably displaced. Attached for free rotation to the distal end of the plunger 130 by a pin 131 is a roller 132 serving as a contacting element in abutting contact with the cam surface 101.